Hemp is often touted as an eco-friendly crop, but what do the latest figures actually show? From CO₂ sequestration to low input requirements and crop yields, here’s a look at the available data that helps shed light on the true carbon footprint of this plant.

Things to remember

• Hemp can absorb approximately 9 to 15 tons of CO2 per hectare as it grows.

• Its cultivation generally requires fewer pesticides, fertilizers, and water than some industrial crops.

• The overall carbon footprint also depends on how the hemp is processed and the end use of the products.

Key statistics on carbon sequestration from hemp

CO2 capture per hectare

The first indicator studied by the researchers concerns a crop's ability to absorb carbon dioxide.

For hemp, the most common estimates put this sequestration at between 9 and 15 tons of CO2 per hectare during growth. This performance can be attributed to several factors. 

The plant produces a lot of biomass, that is, plant matter. It also has adeep root system that promotes nutrient uptake and carbon storage in the soil.

Some of the carbon absorbed remains stored in the plant's fibers, stems, and seeds.

This characteristic explains why hemp is often studied in research on crops that can help reduce atmospheric carbon.

Comparison with other crops

When comparing different crops, hemp often performs well.

Some estimates suggest, for example, that hemp can sequester between 9 and 15 tons of CO2 per hectare, whereas crops such as corn or cotton generally capture much less.

These figures vary, of course, depending on climate, soil quality, and farming practices, but they show that hemp has significant environmental potential.

However, we should exercise caution when making direct comparisons. The total carbon footprint of a crop does not depend solely on CO2 uptake during its growth.

A crop that requires relatively few inputs

Fewer pesticides in many cases

Another important factor in thecarbon footprint of a crop involves the use of agricultural inputs.

Inputs include pesticides, herbicides, and chemical fertilizers. Their production and use can generate greenhouse gas emissions.

Hemp is naturally resistant to many pests. It also grows quickly, which limits competition with certain weeds. In many cases, farmers can therefore reduce their use of pesticides.

Moderate water consumption

Compared to certain industrial crops such as cotton, hemp generally requires less irrigation. Its deep root system allows it to utilize the water in the soil relatively efficiently.

The Role of Hemp in Low-Carbon Materials

Carbon sequestration in products

The environmental impact of hemp also depends on what is done with the plant after harvest.

When hemp fibers are used to manufacture sustainable materials, some of the carbon captured during growth remains stored in these products.

This is particularly true of certain hemp-based building materials. Recent research shows that some materials, such as hempcrete, can have a very low carbon footprint—or even a negative one under certain conditions.

A very versatile plant

Hemp has another advantage: almost every part of the plant can be used.

The fibers are used in textiles or bio-based materials. The seeds can be used in food. The CBD flowers are used in wellness products, particularly for CBD extraction.

This versatility makes it possible to utilize a large portion of the biomass produced. When the plant is fully utilized, the environmental impact per final product can be reduced.